The period immediately after hospital discharge is a particularly risky time for patients who are being discharged from a high-care setting. Discharged "sicker and quicker" (Kosecoff et al., 1990), patients abruptly move from the hospital's high care setting to a home environment with little support or follow-up. A recent study published in the Annals of Internal Medicine reported that nearly 20% of patients experienced adverse events in the fourteen days after discharge with a third of these events causing a significant disability (Forster et al., 2003). Adverse drug events and procedure-related injuries were the most common complications. Nearly 75% of these complications were judged preventable or ameliorable if they had been detected in a timely manner. Through NIH funded research, Talaria has developed the CareWave monitoring system which uses two-way interactive messaging delivered to mobile wireless devices to provide high intensity, continuous care for patients taking complicated HIV drug protocols, individuals in alcohol treatment, and for patients starting outpatient treatment of depression. The CareWave system allows close surveillance of patients via direct inquiry for early detection or prevention of adverse events as well as supplying messages designed to offer psychosocial support and improved treatment adherence. The CareWave Sentinel application proposes to build on Talaria's experience with two-way interactive wireless messaging and prototype a system to support patients in the transition from the highly supportive healthcare environment to home, a time when patients are most vulnerable to complications. Ultimately, this technology has the potential to decrease adverse events and patient disability, maximize provider time, and reduce overall medical costs. In Phase I, we will create content to support a group of patients who have undergone an interventional pain management procedure, enhance the CareWave system to accommodate the new functionality, and evaluate the monitoring system in two groups of patients who will be randomly assigned to use the CareWave system or to a usual care condition. In Phase n, we will broaden the content, expand the technology, and increase the use of the CareWave for patients with a greater number of medical conditions as well as perform a clinical trial to Care Wave's effectiveness.